X t tightening



T. DAVIS.

TIGHTENING DEVICE. APPLICATION m50 JULY 20.19r8.

Patented' Febf 1, 1921t ation'. an.,

UNITED STATES PATENT OFFICE.

-rIe-HTENING V DEVICE.

needed/r.

Application filed July 20, 1918.

To all' ioiom 'it may concern VBe it known that l, fifi-reruns Davis, a citieen of the United States, residing` in Ulnnulgee county and State of Oklahoma, have invented certain new and useful improve ments in Tightening evices, of which the following is a specitlcation, reference being had to the accompanying drawings.

This invention relates to an improved tightening device for the belts of radiator tane such as are commonly used in connection with vehicle motors, and has for its primary object to provide a device primarily designed for use in connection with a well known type of vehicle motor, whereby the fan belt may be properly adjusted and maintained at the desired tension.

it is another object of the invention to provide a device applicable to the vehicle motor without necessitating any alterations whatever' in the fan shaft moiuitino.

lt is a more particular object of the inn vention to provide a device for the above purpose consisting of a resilient element adapted to be secured at one of its ends by the adjust-ing bolt .for the fan shaft bracket, and an adjustable connection. between the other end of said element and the shaft braclret, whereby the bracket may be prop erly adjusted to tighten the belt.

11nd it is a further general object of my invention to provide a device for the above p pose which is exceedingly simple as well as durable in its construction, highly serviceable and convenient for the purpose in view, and which can be manufactured, and` sold at relatively small cost.

lilith the above and other objects in view, the invention consists in the improved con struction, combination and arrangement of the several parts as will be hereinafter more fully described, subsequently claimed and illustrated in the accompanying drawing in which similar reference characters designate corresponding parts throughout the several views, and wherein Figure 1 is a rear end elevation of the fa shaft mounting illustrating the preferred embodiment of my improved tightening device in its applied position;

Fig. 2 is a plan view; and

Figs. 3 and il are perspective views of the parts of the device disassembled.

Referring in detail to the drawing, where* in l have illustrated the mounting and arrangement of the radiator fan as found in Specification of Letters Patent.

Serial No. 245,887.

the Ford motor vehicle construction, 5i designates the fan shaft bracket which is mounted at one of its ends for swinging or pivotal movement upon the bolt 6. rLhis end of the bracket is formed with a toe or extension 7 which is engaged by a set screw 8 threaded in a lug 9 on the casing which houses the cam shaft gears of the motor. In the-other end of the bracket 5, the fan shaft l() is journaled, and has the fan 11. hxed to its forward end. Between the bracket and the fan, the belt wheel 12 is fixed on the shaft 10 around which the belt 13 is engaged which extends from a similar wheel fixed upon the motor shaft. lt will be understood that all of the parts just described constitute the fan shaft mounting as now in general use and comprise no part of my invention. The adjusting screw 8 permits of a very limited range of adjustment of the fan shaft bracket. By means of my invention which I shall new proceed to describe in detail, the tension upon the fan belt may be more precisely regulated in accordance with the strength of the belt, and the objection to the adjustable set screw above noted obviated.

\ With the above end .in view, l provide a rod of resilient spring metal having a single coil 14 formed therein. One end 15 of this coil is extended in radial relation thereto and terminates in an eye 16, which is adapted to receive the set screw or bolt 8 above referred to and to be secured between the head of said bolt and the lug 9. The other end'17 of the rod 14 projects in an opposite direction tangeutially from the coil 15 and also terminates in an eye 18. The threaded end of a rod 19 is engaged through this latter eye. Upon the other end of said rod, a hook 20 is formed. This hoolr is adapted for engagement around the far side of the bracket 5 at the rear thereof. An adjusting nut 21 is threaded upon the end of the rod 19 and by engagement with the eye 18 draws the rod through said eye to swing the bracket and angularly position the same with relation to the axis of the supporting bolt 6. A lock nut 22 for the nut 21 is also threaded' upon the end of the rod 19. V'It will thus be apparent that by adjusting the nut 21 to swing the bracket upwardly, the fan shaftl will be raised and the belt tightened upon the wheel 12. If the belt is of weak construction, the adjustment should not be made too tight, as the belt would be Patent-d Feb. 1, 1921.

liable to break. If a belt of chain or other metal construction is employed, this probability does not exist and the adjustment may be made very solid and strong. By providing the resilient tension applying element 14, the tension may be regulated to a nicety, and violent shocks or jars to which the motor may be subjected will be absorbed by this tensioning element, whereby the ble breakage of the bracket or the fan is obviatec.

From the foregoing description, taken in connection with the accompanying drawing, the construction, manner of application and use, and several advantages of the invention Will be clearly and fully understood. It will be seen that the device can be readily applied in its operative position without necessitating any alterations whatever in the fan mounting with which the motor is equipped. The several parts of the device are of very simple form so that the tensioning device will be strong and durable, as wellv as serviceable and efficient in practical use, and. likewise capable of manufacture at comparatively small cost.

While I have herein shown and described the preferred form and construction of the various elements, it is to be understood that the device is susceptible of considerable modification therein and I, accordingly, reserve the privilege of adoptingall such le gitimate changes as may be fairly embodied within the spirit and scope of the invention as claimed.

I claim In a tightening device, a support having an upstanding bearing, a fan shaft bracket having a bearing for a fan shaft and propossishaft vided with a radial lug alined with the bracket, means passing through the bracket adjacent where the lug unites therewith and pivotally mounting the bracket on said bear ing, an adjusting screw mounted on and carried by the support and adapted to coper ate with the lug to limit the bracket in its movement in one direction, a single coil spring disposed in a plane with the bearing and being detachably carried on the screw, said single coil having a relatively rigid arm, a screw carried by the terminal of the rigid arm, nuts on opposite sides of the rigid arm terminal and being adjustably threaded to the second screw for holding the second screw adjusted and in a position at right angles to the arm, one end of the second screw terminating in a hook engaging the fan shaft bracket, said rigid arm being oil'- set to the side and in a plane slightly in advance of the bracket and having its terminal disposed at a point below thc fan shaft, whereby should the belt break, the bracket will wipe frictionally against the second screw and then contact with one of the nuts and limit the bracket in its movement and at the same time cushion the bracket and rebound it in contact with the hook, said second screw adapted to be adjusted to increase or decrease the tension of the coil and thereby increasing or decreasing the tightness of the belt.

In testimony whereof I hereunto ailix my signature in the presence of two witnesses.

THOMAS DAVIS.

Witnesses JACOB Bonomms, J. G. MORRIS. 

